R.F. conductivity in copper at 8 mm wavelengths

Abstract
Measurements of r.f. conductivity in copper have been made at 8mm wavelengths. It is shown that, in addition to the known effect of surface roughness, the conductivity may be considerably reduced below the d.c. value by surface layers of low conductivity and stress in the bulk material. This can be overcome by etching and annealing, or by a process designed to cover the surface layers. Under suitable conditions the d.c. conductivity can be obtained.